Method and apparatus for heating oil pumped from an oil well

ABSTRACT

The specification discloses an apparatus and method for breaking down the water-paraffin emulsion in oil to facilitate the separation of the water from the oil. The system includes a combustion engine for pumping the oil to the surface and a heat exchanger having a shell with a first inlet for receiving the oil and a first outlet for discharging the oil. A second inlet is formed in the heat exchanger for receiving the exhaust gases from the engine and is connected to at least one heat exchanger tube disposed within the shell, whereby the oil being passed through the shell surrounds the heat exchanger tube and absorbs the heat transferred to the tube by the flow of the exhaust gases therethrough. A second outlet in the heat exchanger communicates with the heat exchanger tube and contains an adjustable baffle for varying the speed of the flow of exhaust gases through the tube, thereby varying the amount of heat available to be transferred to the oil passing around the tube.

[4 1 July 1,1975

[ METHOD AND APPARATUS FOR HEATING OIL PUMPED FROM AN OIL WELL Arthur B.Wells, P. O. Box 489, Jacksboro, Tex. 76056 [22] Filed: Nov. 29, 1973[21] Appl. No.: 420,213

[76] Inventor:

[58] Field of Search 1 ..210/181, 187, 72, 71; 165/51, 158; 166/265-267,302, 314, 57, 75

[56] Reterences Cited UNITED STATES PATENTS 824,808 7/1906 Pannier165/158 1,308,486 7/1919 Earle 165/51 1,660,230 2/1928 Monger 210/181 X1,745,492 2/1930 Kelch et 211....v 165/51 2,656,925 10/1953 Johnson 4210/187 2,684,762 7/1954 Silley et a]. 1 1 210/187 2,698,055 12/1954Williams 166/267 X 2,864,502 12/1958 May 210/72 Primary Examiner-Stephen.l. Novosad Attorney, Agent, or Firm-Richards, Harris & Medlock 5 7ABSTRACT The specification discloses an apparatus and method forbreaking down the water-paraffin emulsion in oil to facilitate theseparation of the water from the oil. The system includes a combustionengine for pumping the oil to the surface and a heat exchanger having ashell with a first inlet for receiving the oil and a first outlet fordischarging the oil. A second inlet is formed in the heat exchanger forreceiving the exhaust gases from the engine and is connected to at leastone heat exchanger tube disposed within the shell, whereby the oil beingpassed through the shell surrounds the heat exchanger tube and absorbsthe heat transferred to the tube by the flow of the exhaust gasestherethrough. A second outlet in the heat exchanger communicates withthe heat exchanger tube and contains an adjustable baffle for varyingthe speed of the flow of exhaust gases through the tube, thereby varyingthe amount of heat available to be transferred to the oil passing aroundthe tube.

7 Claims, 5 Drawing Figures PATEHTEHJUL '1 STORAGE TANK METHOD ANDAPPARATUS FOR HEATING OIL PUMPED FROM AN OIL WELL FIELD OF THE INVENTIONThis invention relates to a method and apparatus for heating oil tofacilitate the removal of water therefrom, and more particularly to theuse of the heat from the exhaust of the engine of an oil well pump toheat the oil to break down the water-paraffin emulsions within the oilso that the water may be separated from the oil.

PRIOR ART Oil pumped from an oil well generally contains impuritiesincluding paraffin and water. The water is usually trapped in anemulsion with the paraffin, thereby requiring treatment of the oilbefore it may be sold. It is known that heating of the oil causes theparaffin to break down and release the water; once released, the waterfalls to the bottom of the container and may readily be removed.

Heating the oil has generally been heretofore accomplished by the use ofheating units comprising burners fed by gas obtained from the well orfrom a separate source. Such heating techniques present problems insmall wells wherein sufficient natural gas is not available from thewell to operate the burners. In such small wells with insufficientnatural gas to feed the heating units, an expensive outside supply offuel such as butane must be provided. Further, such prior gas heatingtechniques have sometimes been inadequate to break down thewater-paraffin emulsion and a paraffin solvent must be introduced intothe fluid to promote the separation of water and oil.

A need has thus arisen for a technique for economically heating thefluid pumped from an oil well to assist in the removal of water from theoil. The system should be one that can be readily movable from well towell as the pumps are moved from one well to another. Preferably, thesystem should be relatively maintenance-free and of a simplistic designto foster easy repairs when necessary.

SUMMARY OF THE INVENTION The present invention is directed to a systemand apparatus for essentially eliminating or reducing the problemsheretofore associated with apparatus for heating oil to break down thewater-paraffin emulsion for enabling removal of the water from the oil.In accordance with the present invention, heating of the oil isaccomplished through utilization of the hot exhaust gases from theengine driving the well pump. The exchange of heat from the engineexhaust to the oil is accomplished through the use of a shell and tubeheat exchanger. The shell of the exchanger is adapted with a first inletfor receiving the oil from the well and a first outlet for dischargingthe oil after heated. A second inlet is adapted to receive the hotexhaust gases from the engine and a second outlet is joined to thesecond inlet by at least one tube which is disposed within the shell.The heat from the exhaust is transmitted through the tube to the oilflowing around the tube within the shell of the heat exchanger.

In accordance with a further aspect of the invention, the second outleton the heat exchanger is provided with an adjustable baffle for varyingthe speed of the flow of exhaust gases through the tube. By varying theflow of the exhaust gases, an operator may control the heat of the tubeand thus the heat of the oil in contact with the tube.

DESCRIPTION OF THE DRAWINGS For a more complete understanding of thepresent invention and for further objects and advantages thereof,reference is now made to the following Detailed Description, taken inconjunction with the Drawings, wherein:

FIG. 1 shows a somewhat diagrammatic illustration of the presentinvention;

FIG. 2 is an enlarged longitudinal sectional view of the heat exchangerillustrated in FIG. I;

FIG. 3 is an end view of the heat exchanger shown in FIG. 1;

FIG. 4 is a sectional view taken generally along the section line 4-4 inFIG. 2; and

FIG. 5 is an enlarged view of a baffle employed in the heat exchanger.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT Referring now to theDrawings, FIG. 1 discloses a conventional well pump schematically shownby the numeral I0 which reciprocates a rod 12 to pump oil from the wellthrough an outlet I4. An engine I6 drives the well pump 10 in thewell-known manner. Engine 16 may be any combustion type engine, with thehot exhaust gases from the engine 16 being directed to the inlet of aheat exchanger device 18. The oil from the well is pumped through theheat exchange device 18 and the oil is heated by the exhaust gases andis then pumped through a pipe 20 to a storage tank. The heating of theoil causes breakdown of the water-paraffin emulsion within the oil, suchthat the water separates from the oil in the storage tank. The purifiedoil may then be pumped from the container and the water removed.

FIG. 2 shows a sectional view of the device 18, wherein hot exhaustgases from the engine 16 are applied to an inlet 22 and are conducted bythree exchange tubes 24, 26 and 28 to an outlet 30. Outlet 30 opens tothe atmosphere and includes a baffle 32 which may be adjusted in orderto vary the amount of heat provided by the device to the oil. The heatexchange unit 18 is enclosed within an insulating skin 29 which servesto retain the heat from the hot exhaust gases for more efficient heatingof the oil. The untreated oil from pump 10 is carried from the pump headthrough pipe 14 to an inlet 34 on device 18. The untreated oil passesinto shell 38 and around the tubes 24, 25 26 28 to absorb the heattherefrom. The heated oil then passes out through the outlet 36 fortransmission to the storage tank.

As shown in FIG. 4, the pipes 24, 26 and 28 are symmetrically disposedwithin the shell 38. Of course, additional tubes of various shapes andpositioned in various locations within the heat exchanger may beutilized within the present system. The heat exchange unit is made of amaterial such as stainless steel, which is capable of withstandingrepeated and continuous exposure to the high temperatures encountered bythe unit.

FIG. 5 shows an enlarged view of baffle 32 located within the outlet 30.Baffle 32 is of the butterfly valve type the adjustment of which variesthe flow of exhaust gases through pipes 24, 26 and 28. By varying theflow of the exhaust, the temperature of the tubes may be controlled,thus controlling the temperature of the oil passing over the tubes.

While in the above described embodiment of the invention, the engineexhaust is directed through the heat exchanger tubes and the oil ispassed into the heat exchanger shell and allowed to flow around thetubes. it is readily apparent that the routing of the oil and theexhaust gases may be interchanged such that the oil is made to flowthrough the tubes and the exhaust gases are made to flow around thetubes to heat the oil therein.

The present invention eliminates the expense and inconvenience ofsupplying expensive fuel and equipment for heating the oil and the needfor a paraffin solvent. Utilization of the exhaust from the pump engineas a means of heating the oil eliminates the need for a separate burnerunit, as well as the need for a fuel source to feed the burner. It hasalso been found that due to the degree of heat available through thismethod, the need for a paraffin solvent is in many cases also eliminatedwhile still achieving the degree of purity necessary to sell the oil.

The present invention is particularly suitable for taking advantage ofthe high temperature of the oil upon emergence from the ground. Themobility of the present invention and the proximity of the pump engineto the mouth of the well allow the earliest possible heating of the oilupon removal from the well.

Although the well heater unit shown in the Drawings comprises thepreferred embodiment of the present invention, it will be understoodthat numerous other embodiments can be employed in the practice of theinvention. For example, various heat exchanger designs may be employedto successfully utilize the heat from the exhaust of the engines to heatthe oil flowing from the pump.

Although specific embodiments of the invention are illustrated in theDrawings and described herein, it will be understood that the inventionis not limited to the embodiments disclosed but is capable of rearrangement, modification and substitution of parts and elements withoutdeparting from the spirit of the invention.

What is claimed is:

l. A method of breaking down water-paraffin emulsion in oil comprising:

moving oil from a well with a motor which emits heated exhaust gases;passing the exhaust gases from the motor through a plurality of confinedpaths in a heat exchanger;

passing all of the oil pumped from the well around said confined pathsin said heat exchanger in order to heat the oil to an extent that thewater-paraffin emulsion is broken.

2. An apparatus for breaking down the water-paraffin emulsion in oil asthe oil is removed from an oil well comprising:

an oil well pump motor which emits heated exhaust gases as said motorpumps the oil from the well;

a shell having an inlet for receiving all of the oil pumped from thewell and an outlet for discharging the oil; at least one tube memberdisposed within said shell with both ends of said tube protrudingthrough said shell and with the first end of said tube being adapted toreceive the exhaust gases from the motor whereby all of the oil pumpedfrom the well is heated by the exhaust gases to an extent that thewater-paraffin emulsion is broken 3. The apparatus according to claim 2wherein the second end of said tube contains an adjustable baffle forvarying the flow of exhaust gases through said tube whereby the heattransferred to said tube is regulated. 4. The apparatus according toclaim 3 wherein said shell is enclosed within an insulating skin.

5. Apparatus for heating oil to break down waterparaffin emulsion toenable removal of water from the oil comprising:

a combustion engine for pumping the oil; a heat exchanger having a shellwith a first inlet for receiving all of the oil pumped from the well anda first outlet for discharging the oil;

said shell further having a second inlet adapted to receive the exhaustgases from said engine and a second outlet joined to said second inletby at least one tube disposed within said shell;

means for feeding the exhaust gases from said engine to said secondinlet;

means connected to the outlet of said oil well pump for directing all ofthe oil pumped from the well into said first inlet, whereby all of theoil pumped from the well, when passed through said shell, surrounds saidtube and absorbs the heat transferred to said tube by the flow ofexhaust gases therethrough.

6. The apparatus for heating oil to break down waterparaffin emulsionaccording to claim 5 wherein said second outlet on said heat exchangercontains an adjustable baffle for varying flow of exhaust gases throughsaid tube to thereby vary the heat transferred to said tube.

7. A method of breaking down water-paraffin emulsion in oil comprising:

moving oil from a well with a motor which emits heated exhaust gases;

passing the exhaust gases from the motor through a heat exchanger;

passing all of the oil pumped from the well through said heat exchangerin order to heat the oil to an extent that the water-paraffin emulsionis broken; and

varying the flow of exhaust gases through said heat exchanger to therebyvary the heat transferred from the gases to said heat exchanger.

1. A METHOD OF BREAKING DOWN WATER-PARAFFIN EMULSION IN OIL COMPRISING:MOVING OIL FROM A WELL WITH A MOTOR WHICH EMITS HEATED EXHAUST GASES,PASSING THE EXHAUST GASES FROM THE MOTOR THROUGH A PLURALITY OF CONFINEDPATHS IN A HEAT EXCHANGER, PASSING ALL OF THE OIL PUMPED FROM THE WELLAROUND SAID CONFINED PATHS IN SAID HEAT EXCHANGER IN ORDER TO HEAT THEOIL TO AN EXTENT THAT THE WATER-PARAFFIN EMULSION IS BROKEN.
 2. ANAPPARATUS FOR BREAKING DOWN THE WATER-PARAFFIN EMULSION IN OIL AS THEOIL IS REMOVED FROOM AN OIL WELL COMPRISING: AN OIL WELL PUMP MOTORWHICH EMITS HEATED XHAUST GASES AS SAID MOTOR PUMPS THE OIL FROM THEWELL, A SHELL HAVING AN INLET FOR RECEIVING ALL OF THE OIL PUMPED FROMTHE WELL AND AN OUTLET FOR DISCHARGING THE OIL AT LEAST ONE TUBE MEMBERDISPOSED WITHIN SAID SHELL WITH BOTH ENDS OF SAID TUBE PROTRUDINGTHROUGH SAID SHELL AND WITH FIRST END OF SAID TUBE BEING ADAPTED TORECEIVE THE EXHAUST GASES FROM THE MOTOR WHEREBY ALL OF THE OIL PUMPEDFROM THE WELL IS HETED BY THE EXHAUST GASES TO AN EXTENT THAT THEWATER-PARAFFIN EMULSION IS BROKEN.
 3. The apparatus according to claim 2wherein the second end of said tube contains an adjustable baffle forvarying the flow of exhaust gases through said tube whereby the heattransferred to said tube is regulated.
 4. The apparatus according toclaim 3 wherein said shell is enclosed within an insulating skin. 5.Apparatus for heating oil to break down water-paraffin emulsion toenable removal of water from the oil comprising: a combustion engine forpumping the oil; a heat exchanger having a shell with a first inlet forreceiving all of the oil pumped from the well and a first outlet fordischarging the oil; said shell further having a second inlet adapted toreceive the exhaust gases from said engine and a second outlet joined tosaid Second inlet by at least one tube disposed within said shell; meansfor feeding the exhaust gases from said engine to said second inlet;means connected to the outlet of said oil well pump for directing all ofthe oil pumped from the well into said first inlet, whereby all of theoil pumped from the well, when passed through said shell, surrounds saidtube and absorbs the heat transferred to said tube by the flow ofexhaust gases therethrough.
 6. The apparatus for heating oil to breakdown water-paraffin emulsion according to claim 5 wherein said secondoutlet on said heat exchanger contains an adjustable baffle for varyingflow of exhaust gases through said tube to thereby vary the heattransferred to said tube.
 7. A method of breaking down water-paraffinemulsion in oil comprising: moving oil from a well with a motor whichemits heated exhaust gases; passing the exhaust gases from the motorthrough a heat exchanger; passing all of the oil pumped from the wellthrough said heat exchanger in order to heat the oil to an extent thatthe water-paraffin emulsion is broken; and varying the flow of exhaustgases through said heat exchanger to thereby vary the heat transferredfrom the gases to said heat exchanger.